Effect of AC Electric Field Polishing on Motion of Slurry and Tool Edge Surface

This paper describes AC electric field polishing (EFP) effects on polishing slurry and cutting tools. The authors evaluate a novel polishing method intended to reduce tool edge wear. The developed polishing apparatus uses free-abrasive control technology and an AC electric field. Results show increased flank wear was suppressed when using an AC electric field. As a detailed investigation of the EFP mechanism, this study explored the AC electric field effects on the polishing slurry and the tool edge surface after EFP. After evaluating the polishing slurry behavior around a tool edge in an AC electric field, we confirmed the abrasive motion around a tool edge in an AC electric field. Diamond abrasives gathered around the tip of the cutting tool edge, even when the tool edge and the polishing pad were separated in an AC electric field. Furthermore, the AC EFP effects on the cutting tool were evaluated. To clarify the AC electric field effects, we measured the surface roughness of the edge and the radius of curvature of the cubic Boron Nitride (cBN) and Cermet tool after polishing with and without an AC electric field. The surface roughness with an AC electric field was less than that without an AC electric field. Finally, a hypothesis was presented for the edge surface effect on EFP. The polishing slurry, which is synchronized with the applied voltage cycle, gathers in the electric field generated along the tool's cutting edge shape. Results suggest that abrasives gathered by the AC electric field can remove weak areas of the sintered cBN cutting-tool-edge surface. Only the strong bonded portion is likely to remain during polishing.